 In Zeise's salt K[PtCl3(C2H4)].H2O the C−C bond length has increased to 134 picometres from 133 pm for ethylene.In the nickel compound Ni(C2H4)(PPh3)2 the value is 143 pm.The interaction also causes carbon atoms to "rehybridise" from sp2 towards sp3, which is indicated by the bending of the hydrogen atoms on the ethylene back away from the metal.